page_title: Minidoka Project
section_title: Facilities
hierarchical_section_title: Minidoka Project / Facilities
caption_attribution_description: English: Island Park Dam. Henrys Fork. Fremont County Idaho
context_page_description: The Minidoka Project is a series of public works by the U.S. Bureau of Reclamation to control the flow of the Snake River in Wyoming and Idaho, supplying irrigation water to farmlands in Idaho. One of the oldest Bureau of Reclamation projects in the United States, the project involves a series of dams and canals intended to store, regulate and distribute the waters of the Snake, with electric power generation as a byproduct. The water irrigates more than a million acres of otherwise arid land, producing much of Idaho's potato crop. Other crops include alfalfa, fruit and sugar beets. The primary irrigation district lies between Ashton in eastern Idaho and Bliss in the southwestern corner of the state. Five main reservoirs collect water, distributing it through 1,600 miles of canals and 4,000 miles of lateral distribution ditches.
context_section_description: The project's dams and reservoirs comprise:
  Jackson Lake Dam in Grand Teton National Park, which raises the elevation of the natural glacial Jackson Lake by 30 feet (9.1 m), with a storage capacity of 847,000 acre feet (1.045 km³).
  Grassy Lake Dam is located in Wyoming in Bridger-Teton National Forest between Yellowstone National Park and Grand Teton National Park, directly adjacent to the south boundary of Yellowstone. Built between 1935 and 1939, Grassy Lake Dam is 118 feet (36 m) high with a capacity of 15,200 acre feet (0.0187 km³) on Grassy Creek. Grassy Creek's flow was not sufficient to supply the reservoir reliably, so water from Cascade Creek was diverted by a 14 feet (4.3 m) dam and diversion canal 0.7 miles (1.1 km) long. The lands around Grassy Lake and Island Park Reservoirs are administered by the U.S. Forest Service.
  Island Park Dam on the Henrys Fork of the Snake River, 38 miles (61 km) north of Ashton, Idaho. The 91 feet (28 m) dam has a storage capacity of 135,000 acre feet (0.167 km³). It was built at the same time as Grassy Lake Dam. Along with the Grassy Lake Reservoir, the Cross Cut diversion dam and the Cross Cut Canal, it forms the Upper Snake River Division of the Minidoka Project. The canal moves water from the Henrys Fork into the Teton River.
  American Falls Reservoir on the main branch of the Snake River, is the largest reservoir in the Minidoka Project, impounded by American Falls Dam. The original dam was built between 1925 and 1927, and was replaced between 1976 and 1978. Reservoir capacity is 1,672,600 acre feet (2.0631 km³). Construction of the dam and reservoir required the relocation of most of the town of American Falls, with many existing structures relocated.
  Lake Walcott, impounded by Minidoka Dam on the Snake. Minidoka Dam started construction in 1904 to provide irrigation and power. The lake has a capacity of 210,200 acre feet (0.2593 km³). The power plant was one of the first to be installed in a Bureau of Reclamation project, providing power principally for pumping operations. Much of Lake Walcott is within Minidoka National Wildlife Refuge, providing habitat for waterfowl. The dam and powerplant are listed on the National Register of Historic Places.
  The five main reservoirs are connected by a network of canals and pumping stations to regulate and distribute the water, supplying more than 1 million acres (4,000 km²).
caption: Island Park Dam
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